Natural products, while often safe, are generally expensive and do not have biocidal efficacy against a broad spectrum of organisms such as gram negative and positive bacteria and fungi. Most natural products are only effective against gram positive bacteria at relatively high concentrations and are not effective against gram negative bacteria or fungi.
Cinnamaldehyde is a natural product which has been used (1) as a flavoring agent, (2) in preservative systems, and (3) to control insect and arachnid populations. See U.S. Pat. Nos. 4,525,480, 5,306,707, 5,536,501, 5,676,958, and 5,839,224.
There is a continuing need for low cost and safe preservative systems which are effective against a broad spectrum of microorganisms.